干旱胁迫对油茶组培苗与实生苗内源激素含量的影响

摘要

为了更深层次地了解油茶的耐旱机理,研究了干旱胁迫对油茶组培苗和实生苗内源激素含量的影响.结果表明,在干旱胁迫下,内源脱落酸(ABA)含量升高,玉米核苷(ZR)、赤霉素(GA3)含量下降,吲哚乙酸(IAA)含量则是先升后降,2种繁殖方式培育的苗木内源激素含量的变化趋势一致,且变化的幅度差异不显著,从ABA含量变化的角度推断组培苗的抗旱性与实生苗可能没有差异.激素间比值分析结果显示,组培苗与实生苗中ZR/ABA比值都呈降低趋势,ZR/IAA比值变化呈先降后升的波动形式,ABA/(IAA+GA3+ZR)总体呈升高趋势,在处理后期ABA/(IAA+GA3+ZR)比值出现缓慢降低,提示受试植株可能在适应了重度缺水的情况下,内部建立了新的激素平衡,在这种激素平衡的调节下,植株仍呈现出朝向生长的方向发展的趋势.这种内源激素调节能力,在2种繁殖方式培育的油茶苗中都有体现,可能是油茶这一种属的特性,也可能是油茶可以耐干旱的内因之一.%In order to learn mechanism of drought stress in Camellia oleifera,effects of drought stress on endogenous hormones contents in tissue culture seedling and seed seedling of C.oleifera were studied.The results show that under drought stress,the ABA content is increased,the ZR and GA3 contents are decreased,while the IAA content is firstly increased and then decreased.Meanwhile,the variation trends of endogenous hormones in tissue culture and seed seedlings under drought stress are accordance,and the variation amplitudes have no significant differences.According to variation of the ABA content,it is deduced that drought resistances between tissue culture and seed seedlings probably have no difference.The ratio of ZR/ABA is decreased,the ratio of ZR/IAA is firstly decreased and then increased,and theratio of ABA/(IAA+GA3+ZR) is increased in general.The ratio of ABA/(IAA+GA3+ZR) is slowly decreased at the end of the test,which implicates the tested plants rebuilt a new balance of endogenous hormones while adapting for drought stress,so the tested plants show a growth trend under the new balance of endogenous hormones.The adjustment ability of endogenous hormone has been found in both tissue culture seedling and seed seedling of C.oleifera.The ability probably is the feature in C.oleifera,and also probably is an internal cause of drought tolerant.